These are soft, fluffy high-protein Japanese Castella cupcakes. Light, spongey, and delicately golden — a delicious low-carb treat with the classic melt-in-your-mouth texture!
Why You’ll Love This Recipe
- Soft, airy texture and perfect golden color
- High protein from eggs and protein powder
- Light and not overly sweet
- Great for snacks, dessert, or tea time
- Low carb and sugar-free
Ingredients (Makes 8–10 cupcakes)
- 4 large eggs, room temperature
- ⅓ cup allulose or preferred sugar-free sweetener
- 1 tsp vanilla extract
- ¼ cup almond flour
- 2 tbsp coconut flour
- ¼ cup unflavored or vanilla whey protein powder
- ½ tsp baking powder
- Pinch of salt
- 2 tbsp melted butter or coconut oil (cooled slightly)
- Optional: 1 tbsp heavy cream for extra moisture
Instructions
- Preheat oven to 325°F (160°C). Line a muffin tin with paper liners.
- In a large bowl, beat the eggs and sweetener with an electric mixer on high speed for 5–7 minutes until very thick, pale, and tripled in volume (ribbon stage).
- Gently mix in the vanilla extract.
- In a separate bowl, whisk together almond flour, coconut flour, protein powder, baking powder, and salt.
- Sift the dry ingredients over the egg mixture in 2–3 additions, folding gently with a spatula to keep the batter airy.
- Fold in the melted butter (and cream if using) until just combined.
- Divide the batter evenly into the liners (fill about ¾ full).
- Bake for 18–22 minutes until the tops are golden and a toothpick inserted comes out clean.
- Cool completely on a wire rack. The cupcakes will settle slightly as they cool.
Prep Time: 15 minutes Cook Time: 20 minutes Total Time: 35 minutes
Nutrition (Per Cupcake)
- Calories: ~110
- Protein: 9g
- Total Carbs: 3g
- Net Carbs: 2g
- Fat: 7g
